1. Field of the Invention
This invention relates to cardiovascular surgical apparatus. More particularly, the invention relates to apparatus, a principle function of which is to more safely occlude the ascending aorta during the performance of surgery, such as open-heart surgery or minimally invasive cardiac surgery. Specifically, the invention relates to apparatus which may change size or shape, or both, during such use.
2. Description of Related Art
In many surgical procedures it is necessary to occlude a blood vessel in order to provide the surgeon with a bloodless field in which to work. Such occlusion is most commonly effected by the application of a vascular clamp to the concerned region of the blood vessel. In the performance of most open heart surgical procedures where occlusion of the ascending aorta is essential, however, the use of a vascular clamp for clamping this vessel creates a condition susceptible to serious negative consequences that the surgeon cannot completely control. For example, while the use of a vascular clamp to occlude the aorta provides a quick and easy occlusion of the vessel, clamping the aorta can disrupt the aortic wall, thereby dislodging degenerative plaque-like material, which is capable of migrating to the brain thereby resulting in a stroke. Other consequences can also result from clamping the aorta. For example, the dislodged particles may migrate to other parts of the body thereby creating the danger of limb gangrene in the extremities, such as the arms or legs, or damage to certain organs as, for example, the kidney, the liver or the small or large bowel. Alternatively, in clamping the aorta, the wall may rupture thereby resulting in hemorrhage. Each of these complications can cause serious morbidity and often times may result in death.
It is to the amelioration of these problems, therefore, to which the present invention is directed.